There are two more problems: 1) Most importantly, responsibility and justice must be on an individual level: An individual has absolutely no responsibility for

There are two more problems: 1) Most importantly, responsibility and justice must be on an individual level: An individual has absolutely no responsibility for the actions of others who happen share some characteristics with them. If I'm short, I'm not responsible for what other short people do and shouldn't suffer any consequences from it. 2) Profiling leads to many false-positive errors. Consider that even the disparity is so large that 1% of group A and only 0.1% of group B is criminal: * If your customers are 99% group B, you will see ~10 times as many group B criminals as group A. * If you suspect everyone in group A, you'll be wrong and harassing innocent people 99% of the time. The real problem, returning to my first point, is objectifying people: Seeing them as merely threats to your store - like a 2-dimensional character in an action movie - instead of real people with their own lives, feelings and interests. It's much easier to do with people you are unfamiliar with, such as other cultures, races, economic classes, etc.